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Time travel - moving between points in time – has been a topic for science fiction for decades. Films ranging from Doctor Who to Star Trek have seen getting into a vehicle of some sort and arriving in the past or future, ready to take on new adventures. The , however, is much more unclear. While some scientists claim that time travel is possible others say, even if it were, it would be for humans to try it.

For Albert Einstein, the 20th century’s greatest physicist, time is relative. It does not equally for everyone. His theory of special relativity says that time slows down or speeds up on how fast you move compared with something else. the speed of light, a person inside a spacecraft would be much younger than his twin on Earth. In the same way, astronauts who are sent into space slightly slower than they would on earth.

According to the American space NASA, there are scenarios that would make travelling back and forth in time imaginable. One would be through wormholes, bridges between certain points in space and time. While theoretically possible, we do not even know if wormholes exist. In addition, we are far from creating a that would let us move through them.

Besides the physics problem, time travel may also come with some unique situations. A classic example is the grandfather effect, in which a time goes back and kills his parents or his grandfather – the main in the “Terminator” movies – so that he is never born or his life is forever changed. If that were to happen, some physicists say you would not be born in one parallel universe but still be born in another.


A large number of scientists with all the above-mentioned options. They claim that time travel will never work because it is mathematically impossible. In addition, nobody could traveling at the speed of light. Despite these bleak , we can still time travel through movies, television and books.